1. to become smaller, fewer, or less; to decrease
2. to politely refuse an offer or invitation
3. to become worse in quality, condition, or strength

1. a gradual decrease in amount, quality, or importance
2. the process of becoming worse or weaker

Examples

• Sales have declined by 15% this quarter.
• She politely declined the dinner invitation.
• His health began to decline after the surgery.
• The decline in student enrollment worried the school board.
• The company’s decline was gradual but steady.
• I must decline your generous offer.
• The decline of the Roman Empire took centuries.